The proposed research deals with the acquisition, use, and transfer of American Sign Language (ASL) using chimpanzees as subjects. The research may be viewed as a confirmation and extension of previous research undertaken by the Gardners (Gardner and Gardner, l971a), with the primary emphasis on expanding our knowledge concerning the communication abilities of the chimpanzee. Preliminary research at the Institute for Primate Studies, University of Oklahoma, indicates that the Gardner's original findings are replicable. It has also indicated that the use of ASL by chimpanzees as a mode of communication may have far-reaching implications for the study of linguistics, psycholinguistics, and learning, as well as anthropology and animal behavior. The first proposed study attempts to determine those variables that affect the rate of acquisition of signs in chimpanzees. Specifically, learning by imitation and molding (physically forming the sign for the chimpanzee) will be compared using reward or no reward at different levels of vocabulary size in several Chimpanzees. We hypothesize that as the chimpanzee's ability to use ASL improves, reward will be less necessary in training, and imitation will also become more effective. The next series of studies involves communication between chimpanzees using ASL. These studies are designed to determine (a) if chimpanzees will use ASL in communicating with each other (preliminary evidence indicates this is so) (b) if transfer of signs from one chimpanzee to another will occur (i.e., "social transfer"), (c) if chimpanzees will create a sign for an object when they do not already have a sign for that object in their vocabulary, and (d) if dominance relationships will influence the social transfer of ASL between colony members. Finally, the rule-following behavior (syntax) of chimpanzees using ASL will be studied. There are two purposes of the proposed research. First, the studies have implications for the study of animal behavior and primatology. Second, the studies are an attempt to determine if the use of ASL by chimpanzees is a behavior similar to human language.